Bending-type friction steel truss coupling beam for quick recovery after earthquake

ABSTRACT

The disclosure provides a Bending-type Friction Steel Truss Coupling Beam, which can be rapidly repaired following an earthquake event. It comprises an upper chord, a lower chord, a diagonal web member, a web member, a T-shaped plate and a friction device. The friction device is located at both ends of the lower chord, where large deformation may occur. The friction device comprises a T-shaped friction main plate, a friction plate, a cover plate and a friction bolt. The disclosure uses a friction device to dissipate energy based on a common steel truss coupling beam. Different sliding loads can be designed according to the seismic precautionary intensity of different regions. The disclosure has the advantages of simple structure, immediate occupancy and low repair cost.

TECHNICAL FIELD

The present disclosure belongs to the technical field of energy dissipation and seismic reduction in civil engineering, particularly relates to a bending-type friction steel truss coupling beam for quick recovery following an earthquake event.

BACKGROUND

Coupling beam is an important seismic energy dissipating member in shear wall and frame-shear wall structure system. It can effectively resist overturning moment by guaranteeing the transfer of force between adjacent wall limbs. Due to the material property limitation, the reinforced concrete coupling beam exhibit relatively weak seismic performance. In recent years, to achieve excellent energy dissipation and ductility performance, the steel structure beam has been proposed. Besides these, steel truss coupling beam has various advantages of steel coupling beam. It has the advantages of saving material, flexible arrangement of the member, convenient replacement, and so on. When the steel truss coupling beam's span height is relatively large, the bending deformation of the steel truss beam mainly concentrates on the chord end under earthquake action. Therefore, steel truss coupling beams dissipate seismic energy mainly through the plastic deformation, and the earthquake input energy is reduced. However, because this deformation is irreversible, it is difficult to repair after an earthquake. It has been proven to be an effective method to reduce the main structure's seismic performance by introducing energy dissipators into the structure. The friction device has the advantages of simple and reasonable friction mechanism, good energy dissipation capacity, less influence by external conditions, convenient manufacture, simple material and easy manufacture, so it has a good development prospect.

SUMMARY OF THE DISCLOSURE

In order to solve the above problems, the present disclosure proposes a bending-type friction steel truss coupling beam for quick recovery after an earthquake. The friction device is located at both ends of the chord with large deformation, to achieve the purpose of energy dissipation through friction, quick repair after an earthquake and low repair cost.

The technical solution of the disclosure:

A bending-type friction steel truss coupling beam for quick recovery after an earthquake is provided, including upper chord 1, lower chord 4, diagonal web member 2, web member 3, T-plate 10 and friction device.

The web member 3 is vertically fixed between the upper chord 1 and the lower chord 4; Two diagonal web members 2, symmetrically with the web member 3 as an axis, are fixed between the upper chord 1 and the lower chord 4, the upper end of the diagonal web member 2 is fixed on end of the upper chord 1, the lower end of the diagonal web member 2 is fixed near lower end of the web member 3; Flanges of the two T-plates 10 are respectively fixed on upper surface of both ends of the upper chord 1;

The friction device comprises a T-shaped sliding plate 5, a friction plate 6, a cover plate 7 and a friction type high-strength bolt 8; the friction plate 6, the T-shaped sliding plate 5, the friction plate 6 and the cover plate 7 are placed under the lower surfaces of two ends of the lower chord 4; flange of the T-shaped sliding plate 5 is provided with a long slot hole to realize sliding; the friction plate 6, the cover plate 7 and the lower chord 4 are all processed with the same circular bolt holes, and the position of the circular bolt hole corresponds to the position of the long slot hole on the T-type friction sliding plate 5; the friction device is connected and fixed with the lower chord 4 through the matching of the friction type high-strength bolt 8 and nut; there is a gap between the cover plate 7, the lower chord 4 and the flange end of the T-type sliding plate 5.

Further, the circular bolt holes on the lower chord 4, friction plate 6 and cover plate 7 are located at the center of the long slot holes on T-type sliding plate 5. This ensures that the displacement of positive and negative sliding is equal when the T-type sliding plate 5 slips.

Further, the gaps between cover plate 7, lower chord 4 and flange ends of T-sliding plate 5 are larger than the displacement of T-shape sliding plate 5 when sliding happens.

Further, a disc spring 9 is installed below the friction type high-strength bolt 8 and nut to prevent the loosening and deformation of the friction type high-strength bolt 8 during the slip of the T-shape sliding plate 5.

Further, the T-plate 10 and the upper chord 1 are welded or bolted. The diagonal web member 2, the upper chord 1 and the lower chord 4 are welded. Web member 3 is welded to the upper chord 1 and the lower chord 4.

Further, brass plate, brake plate and other friction materials are selected as the material of the friction plate 6.

Benefits of this disclosure: the disclosure provides a Bending-type steel truss coupling beam with a friction device for quick recovery after an earthquake, which uses the friction device to dissipate energy based on the ordinary steel truss coupling beam. The disclosure can select different slip loads according to the fortification intensity of different areas. Under small earthquakes, the flexural steel truss beams with friction device do not slip, equivalent to ordinary steel truss beams and provide lateral stiffness for the structure. The friction device dissipates energy in the moderate earthquake case by sliding friction the friction device in moderate earthquake. The friction device consumes the most energy of the earthquake. The disclosure has the advantages of simple structure, immediate occupancy and low repair cost.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a picture to show the structural of the present disclosure.

FIG. 2 is a picture to show the longitudinal sectional view of the friction device position in FIG. 1.

FIG. 3 is a picture to show the transversal view of the friction device position in FIG. 1.

FIG. 4 is a picture to show the hysteresis curve of the Bending-type friction steel truss coupling beam.

In the figures: 1 upper chord; 2 diagonal web member; 3 web member; 4 lower chord; 5 T-type sliding plate; 6 friction plate; 7 cover plate; 8 friction type high-strength bolt; 9 disc spring.

DETAILED DESCRIPTION

The specific embodiments of the present disclosure will be further described below in conjunction with the drawings and technical solutions.

A bending-type friction steel truss coupling beam for quick recovery after an earthquake is provided, which includes upper chord 1, lower chord 4, diagonal web member 2, web member 3, T-plate 10 and friction device.

As shown in FIG. 1, web member 3 is welded vertically between upper chord 1 and lower chord 4; Two diagonal web member 2 are welded between the upper chord 1 and the lower chord 4 with the web member 3 as axial symmetry, the upper end of the diagonal web member 2 is welded on the upper chord 1 end, the lower end of the diagonal web member 2 is welded near the lower end of the web member 3 position; The flanges of the two T-plates 10 are respectively welded to the upper surface at both ends of the upper chord 1. The friction device of the bending steel truss coupling beam is installed on both ends of the lower chord 4, and the friction device comprises a T-type sliding plate 5, friction plate 6, cover plate 7 and friction type high-strength bolt 8; The lower surface of the both ends of the lower chord 4 is installed with friction plate 6, T-sliding plate 5, friction plate 6 and cover plate 7 in turn; The flange of the T-type sliding plate 5 is provided with a long slot hole to enable slipping; The same circular bolt hole is processed on the friction plate 6, cover plate 7 and lower chord 4, and the position of the circular bolt hole corresponds to the center position of the long slot hole on the T-type sliding plate 5. The friction device is connected and fixed with the lower chord 4 through the cooperation of friction type high-strength bolt 8 and nut, and disc spring 9 is placed under the friction type high-strength bolt 8 and nut respectively to prevent loosening and deformation; There is a gap between cover plate 7, lower chord 4 and flange end of T-type sliding plate 5, and the gap is greater than the displacement of T-type sliding plate 5 when sliding, to avoid bearing between lower chord 4 and flange end of T-type sliding plate 5 when sliding.

FIG. 4 shows the bending-type friction steel truss coupling beam's hysteretic curve with friction device in the present disclosure. During the whole process, the resistance of steel truss coupling beam with friction device does not decrease. 

1. A bending-type friction steel truss coupling beam for quick recovery after earthquake, wherein the bending-type friction steel truss coupling beam comprises an upper chord, a lower chord, diagonal web member, web member, T-plate and a friction device; the web member is vertically fixed between the upper chord and the lower chord; two diagonal web member, symmetrically with the web member as an axis, are fixed between the upper chord and the lower chord, upper end of the diagonal web member is fixed on end of the upper chord, lower end of the diagonal web member is fixed near lower end of the web member; flanges of the two T-plates are fixed on upper surface at both ends of the upper chord, respectively; the friction device comprises a T-type friction sliding plate, a friction plate, a cover plate and a friction type high-strength bolt; at both ends of lower surface of the lower chord, the friction plate, T friction sliding plate, friction plate and cover plate are installed in order; flange of the T-type friction sliding plate is provided with a long slot hole to enable slipping; same circular bolt hole is processed on the friction plate, cover plate and lower chord, and the position of the circular bolt hole corresponds to the position of the long slot hole on the T-type friction sliding plate; the friction device is connected and fixed with the lower chord by the friction type high-strength bolt and the nut; the cover plate, there is a gap between the cover plate, the lower chord and the flange end of the T-type sliding plate.
 2. The bending-type friction steel truss coupling beam for quick recovery after earthquake according to claim 1, wherein the circular bolt holes on the lower chord, friction plate and cover plate correspond to central position of the long slot hole on the T-type sliding plate, so as to ensure that the displacement of forward and reverse sliding of the T-type sliding plate is equal.
 3. The bending-type friction steel truss coupling beam for quick recovery after earthquake according to claim 1, wherein the gap between the cover plate, the lower chord and the flange end of the T-type sliding plate is greater than the displacement when the T-type sliding plate slips.
 4. The bending-type friction steel truss coupling beam for quick recovery after earthquake according to claim 1, wherein a disc spring is installed under the friction type high-strength bolt and nut to prevent the friction type high-strength bolt from loosening and deformation during the sliding process of T-type sliding plate.
 5. The bending-type friction steel truss coupling beam for quick recovery after earthquake according to claim 3, wherein the disc spring is installed under the friction type high-strength bolt and nut to prevent the friction type high-strength bolt from loosening and deformation during the sliding process of T-type sliding plate.
 6. The bending-type friction steel truss coupling beam for quick recovery after earthquake according to claim 1, wherein the T-shaped plate is welded or bolted with the upper chord; the diagonal web member is welded to the upper chord and the lower chord, and the web member is welded to the upper chord and the lower chord.
 7. The bending-type friction steel truss coupling beam for quick recovery after earthquake according to claim 3, wherein the T-shaped plate and the upper chord are welded or bolted; the diagonal web and the upper chord and the lower chord are welded; the web and the upper chord and the lower chord are welded.
 8. The bending-type friction steel truss coupling beam for quick recovery after earthquake according to claim 4, wherein the T-shaped plate is fixed with the upper chord by welding or bolt connection; the diagonal web is welded to the upper chord and the lower chord; the web is welded to the upper chord and the lower chord.
 9. The bending-type friction steel truss coupling beam for quick recovery after earthquake according to claim 1, wherein the friction plate is made of brass or brake pad.
 10. The bending-type friction steel truss coupling beam for quick recovery after earthquake according to claim 6, wherein the friction plate is made of brass or brake plate. 